Steam heating system



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9 Sheets-Sheet 1 Original Filed June 22, 1931 Jan. M, W36. F. u. RAYMOND STEAM HEATING SYSTEM Original Filed June 22, 1931 9 Sheets-$heet 2 lanai gymond;

9 F. I. RAYMOND STEAM HEATING SYSTEM Ofiginal Fil ed J'ne 22, 1951 9 Sheets-Sheet 3 Jan. 1, F. l- A STEAM HEATING SYSTEM Original Filed June 22, 1931 9 Sheets-Sheet 4 Jan. 14, 1936. RAYMOND 2,027,8$1

STEAM HEATING SYSTEM Original Filed June 22, 1931 9 Sheets-Sheet 5 fiverzz or/ fled [Ia 072i,

v Jan. 14, 1936. F. LRAYMOND STEAM HEATING SYSTEM Original Filed June 22, 1931 9 Sheets-$heet 8 muWN www/ JPQW 4 Jan. M, 19.36.. F. I. RAYMOND STEAM HEATING SYSTEM Original Filed June 22; 1931 9 Sheets-Sheet 9 5 smN .1 EN m5 NmN Low KN. NR 1| k N RRN m C wk m bk bu N KN Patented Jan. 14, 1936 UNITED STATES PATENT OFFICE Original application June 22, 1931, Serial No. 546,126. Divided and this application August 15, 1932, Serial No. 628,907

22 Claims.

As a preface to the following description of my invention this application for which is a division of my pending application for United States Letters Patent Serial No. 546,126, filed June 22, 1931, it may be stated that in the operation of steam heating systems as commonly provided the steam entering the feeder pipes flows first into those radiators nearest the boiler thereby producing unequal heating of the radiators,

and while this condition is not serious when the system is operated under continuous pressure, it is serious when the system is operated intermittently, as for example when the boiler is fired by a start and stop oil burner, because the radiators nearest the boiler will be heated for a longer time than the others each time the burner operates, and this causes a greater amount of heat to be delivered to the first rooms than to the last rooms.

One of my objects is to provide for the heating up of all of the radiators of a steam heating system substantially simultaneously, as distinguished from the heating of those radiators nearest the boiler before the others thereof become heated, thereby avoiding the objections above noted.

Generally stated my invention consists in improvements in the venting of the air from steam heating systems to the end that the air in the radiators of the systems will remain trapped therein until all of the air has been removed from the steam mains.

Referring to the accompanying drawings:

Figure 1 is a view in elevation of a one-pipe steam heating system embodying my invention.

Figure 2 is a similar view of a modification of the system of Fig, 1 and likewise embodying my invention.

Figure 3 is a similar View of another one-pipe steam heating system in which the steam is fed downward from an overhead steam main, and embodying my invention.

Figure 4 is a similar view of a two-pipe steam heating system embodying my invention.

Figure 5 is a similar view of a modification of the system shown in Fig. 1 and likewise embodying my invention.

Figure 6 is a similar view of a large two-pipe steam heating system wherein the steam is fed 0 to down-feed risers from an overhead steam main and embodying my invention.

Figure 7 is a similar view of another two-pipe steam heating system also embodying my invention. 1 l

55 Figure 8 is a vertical sectional view of aspecial valve forming a part of the system shown in Fig. 7.

Figure 9 is a view in elevation of a steam heating system of the wet return type and embodying my invention.

Figure 10 is a longitudinal sectional view of a check-vent valve forming a part of the installation of Fig. 9.

Figure 11 is a similar view of another vent valve forming a part of the installation of Fig. 9.

Figure 12 is a View in elevation of a steam heating system of the dry return type and embodying my invention; and

Figure 13, a view in sectional elevation of a float-equipped vent valve forming a part of the installation of Fig. 12.

Referring to the system shown in Fig. 1, a boiler 9 supplies steam through a pipe II] to a steam main H, the-steam being supplied from the steam main H to the radiators, represented at l3, through riser pipes 14, the water of condensation from the radiators l3 flowing by gravity back to the boiler 9 through the risers I4, the steam mains H and return lines I5 and I6 connected with the bottom of the boiler 9, the steam main sloping at its opposite ends toward the return lines l5 and It as shown.

Each radiator i3 is equipped with a thermostatic vent valve represented at N which may be of a type commonly used for the purpose of permitting air to escape from the radiator but preventing the escape of steam therefrom, except that the vent valves ll in this case are each provided with a weight or spring (not shown) to hold the air-escape valve against its seat until a predetermined pressure is attained in the radiator equipped therewith.

At the ends of the steam main II similar vent valves represented at It are provided, these valves being designed to open to the passage of air at a pressure considerably below that at which the vent valves ll 'open'to the flow of air therethrough, the air escapement valves proper of the valves is preferably presenting a large area.

In operation this system functions as follows: Assuming the steam main II to be'cold and full of air, generation of steam in the boiler 9 causes steam to flow therefrom throughthe steam main it, resulting in an increase of the pressure in this main thereby forcing the air therein out through the vent valves I8, the vent valves I I remaining closed inasmuch as the latter open at a higher pressure than the vent valves l8, thus venting the steam main before the radiators are vented. Since .the valves I8 are of relatively large capacity, it will not be possible to build up an appreciable pressure in the system until they close. Therefore, the steam supplied to the main I I will flow out to the ends of the latter in preference to flowing into the radiators from which no air can escape at the lower pressure. When steam reaches the ends of the steam main II the vent valves I 8 automatically close by thermostatic action of the steam thereon; and as soon as both of the valves I8 close, further generation of steam in the boiler will increase the pressure in the system to a point where the valves I! open and permit of the discharge from the radiators |3 of the air trapped therein, thus venting the radiators after the steam main has been vented. The steam is thus simultaneously, and at substantially the same pressure, supplied to all of the radiators. By providing the valves I! of small size, it will not be possible for one of these valves to vent air in sufficient volume to prevent further raising of the pressure in the system.

Thus there will be a material increase in pressure in the system when the valves I8 close and this material increase in pressure will cause all of the valves IT to open, even though there may be a slight difference in their opening pressures and effect simultaneous supply of steam to all of the radiators.

Referring to the system shown in Fig. 2, a boiler represented at I9 supplies steam through a pipe to a steam main 2 I, this main supplying steam, through risers 23, to radiators represented at 24 equipped with thermostatic vent valves 25 of standard design.

Condensation from the radiators 24 is returned, by gravity, to the boiler I9 through the risers 23, the steam main 2| and return air lines 26 and 21, the latter opening into the bottom of the boiler I9.

This arrangement also comprises a vacuum pump 28 shown as driven by an electric motor 29, the inlet of this pump being connected with a pipe 3|] which opens into pipes 3| and 32 in communication with the ends of the steam main 2| and the outlet thereof provided with an outwardly opening check valve 34, the pipes 3| and 32 having interposed therein thermostatic traps 33, as for example of standard design.

In operation, the entire system will be held under partial vacuum by the vacuum pump 28 so long as the thermostatic traps 33 are open. Therefore when the boiler I9 starts to generate steam, the steam will flow out to the ends of the steam main 2| rather than into the branch risers 23 and radiators 24, thus venting the steam main before the radiators are vented. As soon as the steam reaches the thermostatic traps 33 the latter automatically close so that further generation of steam in the boiler I9 produces a rise in pressure in the system above atmospheric pressure thereby causing steam to enter all of the risers 23 simultaneously as described in connection with the operation of the system shown in Fig. 1, thus venting the radiators after the steam main has been vented, it being. understood that the rise above referred to of the pressure in the system forces open the vent valves 25 topermit the air to vent from the radiators.

Referring to the system shown in Fig. 3, a boiler represented at 35 connects, by an upwardly extending pipe 36, with an overhead main 31 from which steam is supplied to down-feed risers 38 constituting parts of the main 31 and opening into the pipe 31 at different points along the latter as shown. Each riser 38 is shown as connected by pipes 39 with a vertical series of radiators 48 each of which is provided with a thermostatic vent valve 4| of standard design. The system shown is provided for the supplying of steam to radiators a plurality of which are located on each floor of a building, as for example, and as shown in the drawings, four floors.

The condensation from the radiators 40 flows, by gravity, from the radiators to the risers 38 and thence to float traps 42 of standard design which operate to permit the passage of water to a return line 43 connected with these traps by pipes 44, but which close to the passage of air or steam therethrough.

The system also comprises a vacuum pump represented at 45 the inlet of which communicates with a pipe 46 which extends upwardly into a receiver 4'! in communication at its top with the pipe 43, by a pipe 48, the outlet of the pump 45 and represented at 49 being provided with an outwardly opening check valve 50 like the valve 34 of Fig. 2. The bottom of the tank 41 communicates by a pipe 5| with a boiler-feed pump 52 the outlet of which communicates by a pipe 53 with the bottom of the boiler 35.

The system also comprises thermostatic traps represented at 3B communicating with the lower portions of the down-feed risers 38 by pipes 38 and with the return line 43 by pipes 43,

the traps 38 permitting of the passage of air a from the risers 38 to the return line 43 and the escape therefrom through the check valve 58, by the operation of the pump 45, but closing to the passage of steam.

The operation of this system is similar to that of the system shown in Fig. 2, the only difference being in the addition of the float traps 42 which permit the return line 43 to be used as the air line as well as the condensate return line.

So long as any of the thermostatic traps 38 are'cold indicating that steam has not yet filled the steam main 3'! and risers 38, the system will be maintained under a partial vacuum by the vacuum pump 45 and the air in the radiators 4!] will remain trapped therein. When all the steam traps 38 become closed by the presence of steam therein, the vacuum pump 45 no longer exerts suction on the risers 38, the float traps 42 being closed as they open only responsive to the collection of condensate therein, and thus in the continued operation of the boiler the pressure in the pipes 36, 31 and 38 rises above atmospheric thus forcing the air out of the radiators 48 through the vents 4| and simultaneously supplying steam to all of the radiators.

Referring to the system shown in Fig. 4, which constitutes an embodiment of my invention in a so-called two-pipe steam heating system of common design, the boiler 54 connects by a pipe 55 with a steam main 58 from which steam is supplied through risers 51 to radiators represented at 53. The radiators 58 are provided with thermostatic steam traps 59 which open into a return line 60 discharging through a pipe 3| having a short water leg section 62, into the bottom of a separator 63 equipped with an outwardly opening check valve represented at 64. The separator 63 is connected by a pipe 35 with an alternator 65 as for example of standard design and to whichthe condensate in the separator 63 flows through the pipe 55. The upper end of the alternator 66 connects by a pipe 61 with the steam main 56 and the condensate-outlet of the alternator 66 connects by a pipe 68 with the bottom of the boiler 54. This alternator is provided in accordance with common practice for the purpose of returning condensate to the boiler against pressure.

The upper portion of the separator 63 connects, by pipes 69, with thermostatic traps 10 located at the ends of the steam main 56, the traps 10 being open to the flow of 'air and water therethrough and closing to the passage of steam.

The operation of this system is as follows: The generation of steam in the boiler 54 causes steam to flow through the pipe 55 and into the steam main 56. As the steam progresses into the main 56 it displaces the air therein, the air following the path of least resistance to the atmosphere which is through the steam traps I0, return lines 69, separator 63, and check valve 64 to the atmosphere, rather than through the risers 51, radiators 58, traps 59, return line 60, pipe 6|, with its water leg 62, separator 63, and check valve 64, thus venting the steam main before the radiators are vented. Even without the water leg 62 there would be a greater flow of air from the return line 69 than from the return line 60, but the water leg 62 in the return line 69 produces a definite and positive seal which prevents the how of any air therethrough until the pressure in the return line 60 rises sufficiently above atmospheric pressure to blow the water out of the water leg 62.

Steam will therefore flow along the steam main 56 without branching off into the risers 59, until the steam main 56 is completely filled with steam which causes the thermostatic traps I to close. The closing of the thermostatic traps I0, due to the presence of steam therein, prevents the further escape of steam therethrough and the continued generation of steam in the boiler 50 creates an increase in pressure in the system, this pressure finally becoming sufficient toblow the water from the water leg 62 and permit the escape of air from the radiators 58 through the return line 60, thus venting the radiators after the steam main has been vented. Inasmuch as the steam main 56 is filled with steam, the steam, in the venting of the radiators as stated, will start to flow into'all the radiators substantially simultaneously.

In this arrangement it is desirable, though not necessary, that the piping between the steam traps 59 and the separator be equipped with an inwardly opening check valve as indicated at 6 I which permits breaking of the vacuum in the return line 60 thereby preventing leakage of air into the steam main which, as will be manifest, it is desired be avoided.

Referring to the system shown in Fig. 5, which constitutes an embodiment of my invention in a so-called two-pipe steam heating system equipped with a combination vacuum and condensation return pump, the boiler, represented at II, supplies steam through a pipe I2 to a steam main I3 connected, by pipes M, with radiators I provided with steam traps I6 opening into a return line 'I'I communicating with a pipe "I8 having a lower, water leg, section I9 opening into the bottom of a receiver 89.

Steam traps 8| are provided at the ends of the main I3 these traps being connected with a return line 82 connected with a pipe 03 which opens into the top of the receiver 86.

The receiver 88 forms an element of a combination vacuum and condensation pump structure represented generally at 04 and comprising a vacuum pump 85 the inlet of which communicates with a pipe 86 extending upwardly into the receiver 86 and the outlet of which connects with a pipe 0! having an outwardly opening check valve 88. The structure 84 also comprises a boiler feed pump 89 connected at its inlet, through a pipe 90, with the bottom of the receiver 80 and, by a pipe 9I, with the bottom of the boiler II.

The operation of this system is as follows: In starting this system the vacuum pump 85 will withdraw air from the mains I3 through the steam traps 8I, return line 82, pipe 83, receiver 80, pipe 86, exhausting the air through the check valve 88, the air in the radiators I5 remaining therein due to the greater resistance to flow through the risers I4, radiators I5, return line 11,

pipe I8, and its water leg 19, the steam main thus being vented before the radiators are vented. Steam will therefore be drawn out to the ends of the steam main I3 before the steam branches ofi into the risers 14. Upon the closing of the steam traps BI by the presence of steam therein, and thus throughout the extent of the steam main I3, the suction created by the vacuum pump 85 can no longer be relieved by flow through the traps 8|, pipes 82 and 83 and separator 80, whereupon the vacuum created by the pump increases in the receiver 80 until it is sufiicient to overcome the resistance of the water in the water leg I9 whereupon the water will be blown from this leg and air will then be drawn from all of the radiators substantially simultaneously through the steam trap I6, return line 11, pipes 18, separator 80, pipe 86, pump 35, and check valve 88 to the atmosphere, thus venting the radiators after the steam main has been vented, and as at this time the steam mains I3 are filled with steam, the entry of steam into all of the radiators I5 will occur substantially simultaneously.

Referring to the system shown in Fig. 6 which shows the invention embodied in a large so-called two-pipe steam heating system of a type widely used in tall buildings, and comprising downfeed risers, the elements of this system are substantially the same as those shown in Fig. 5 with the exception that the down feed risers constituteportions of the steam main. In this system the boiler is represented at 92 and connects with a pipe 9-3 opening into an overhead steam main 94 from which down feed risers 95 lead. Each riser 95 is shown as connected by pipes 96 with a vertical series of radiators 91 each of which is provided with a steam trap 98 which opens into a return line 90 connected with pipes I00 opening into a pipe I0! having a lower water leg I02 opening into the bottom of a receiver I03.

At the lower ends of the risers 95 are relatively large thermostatic traps I04 connected with a return line I05 opening into a pipe I06 which communicates with the top of the receiver I63. A combination vacuum and condensation pump is represented at I01, the vacuum pump I08 of which connects at its inlet with a pipe I69 opening into the upper end of the receiver I03 and its outlet connecting with a pipe III) having an upwardly opening check valve III. The boiler feed pump element of this apparatus is represented at II2, this pump connecting at its inlet witha pipe I I3 which opens into the bottom of the receiver I03 and at its outlet with apipe I I4 which opens into the bottom of the boiler 92.

As the system now being described functions in the same manner as the system shown inli'ig'. 5 repetition of the description of the operation appears to be unnecessary.

It will be understood from the foregoing that in the systems shown in Figs. 1 to 6, inclusive, the filling of the steam mains, before flow of steam into the radiators, is accomplished by providing greater resistance to the flow of air through the radiators than from the steam mains thereby insuring the filling of the steam mains before starting to fill the radiators with steam. In other words, air flows from the steam mains at a lower pressure than it does from the radiators.

The invention is also capable of embodiment in a system wherein the air is vented from the radiators at the same pressure as that at which it is vented from the steam mains, Fig. '1 constituting such an embodiment of the invention and employing as an'elernent thereof a special valve, shown in detail in Fig. 8, which operates to cause the air to be forced from the steam main before starting the flow of the air from the radiators.

The system shown in Fig. 7 comprises a boiler II 5 connected with a pipe H6 opening into a steam main II1 connected, by risers H8, with radiators I I9 equipped with steam traps I20 which communicate through branch pipes i2I with a dry return line I22, provided with an inwardly opening check valve I22 for the purpose above explained in connection with check valve 6b of Fig. 4. The steam main H1 and the dry return line I22 connect with pipes I23 and I 24, respectively, which open at their lower ends into a wet return line I25 for draining by gravity into the latter condensation in the lines H1 and I22. The wet return line I25 drains into an alternator I26 of common design which returns the condensate to the boiler through pipe I21 even though the pressure in the boiler may be greater than the pressure in the return line.

The system now being described also comprises a special form of valve represented generally at I28 the details of which are shown in Fig. 8. This valve comprises a casing I29 divided by partitions I30 and I3I into an upper compartment I32, a lower compartment I33, and an intermediate compartment I34. The compartment I32 communicates with the steam line H1 beyond the connection of the latter with the drain pipe I23 and the compartment I33 communicates with the dry return line I 22 beyond its connection with the drain pipe I24; and the compartment I34 connects by a pipe I35 with an outwardly opening check valve I36.

The partitions I30 and I3I contain ports I31 and I38 extending therethrough and with which oppositely facing conical valves I39 and I40 cooperate. The valves I39 and I40 are provided on the stem M! of a thermostatic bellows I42 mounted on the top of the casing I29 this bellows being shown as of the common expansible corrugated chamber type containing liquid that boils at a temperature slightly under that of steam. The valve member I40 is shown as adjustable along the stem MI relative to the valve I39, these valves being so spaced that at no time are both valves seated.

The operation of this system is as follows: Assuming the system to be cold, the starting up of the boiler II5 causes steam to flow through pipe I I6 into the steam main II 1. In the cold condition of the apparatus the valve I40 will be seated to close the port 33 and the valve i39 unseated to open the port I31 whereby the steam main II1 will be in communication through the compartments I32 and I34 with the check valve I36. Thus the air in the steam line II1 will be driven therefrom, the radiators II9 being closed to the escape of air therefrom by the closed condition of the valve I40, thus venting the steam main before the radiators are vented. When the steam main I I 1 becomes filled with steam and the steam contacts with the thermostatic bellows I42, this bellows expands forcing the valve I39 to seated position and closing the port I31 and forcing the valve I40 to open position thereby closing the steam line to the escape of steam therethrough to valve device I28 and opening the dry return line I 22 and consequently the radiators for the escape therefrom of the air therein out through the check valve I36, thus venting the radiators after the steam main has been vented. Inasmuch as the steam line I I1 has been filled with steam before the air may vent from any of the radiators, the actuation of the valve I 28 to close the steam main II1 to the escape of steam therefrom and open the return line I22 to the atmosphere, permits the air in the radiators to escape substantially simultaneously from all of the radiators and consequently the steam will flow into all of the radiators substantially simultaneously.

Referring to the system shown in Figs. 9, 10 and 11, the boiler represented at I43 connects by a pipe I44 with a steam main I45 from which the steam is supplied, through risers I46, to radiators represented at I41. The radiators I41 are provided with thermostatic steam traps I48 which open into a dry return line pipe I49 connected with a pipe I50, the latter opening into a pipe I5I leading into a return trap I52 the outlet of which connects by a pipe I53 with the bottom of the boiler I43, the trap I 52 also being connected with the steam line I44 by a pipe I54.

At the ends of the steam main I 45 are vent valves I55 comprising chambers I56 communicating through their side walls with the ends of the steam main I 45 and through their bottom walls with the upper ends of pipes I 51 which open into the return line pipe I50, the water and air or steam discharging from the steam line I45 into the chambers I56. The chambers I56 are in effect separating chambers in which the water settles to the bottoms thereof and flows out through the pipes I51 to the wet return line pipe I50, air or steam entering the chambers I56 rising to the top of these chambers.

The chambers I56 contain outlet ports I58 shown as opening into supplemental chambers I59 having vents I60 the ports I58 being normally closed by disks I6I located in the supplemental chambers and upwardly displaceable.

The chambers I56 also contain thermostatic valve mechanisms controlling the outlets I58 and comprising expansive elements I 62, shown as bellows, supported on spiders I62 in the chambers I56 and having valves I64 which are normally open but which close when the elements I 62 become heated by contact therewith of steam. The return line I49 is connected with a vent valve I65 (Fig. 10) comprising a casing I 66 open to the line I49 and containing an outlet port I61 in its top wall which opens into a chamber I58 having side vents I69 and housing a disk I10 which is much heavier than the disks I 6| and normally closes the outlet port I61, but which is vertically displaceable to uncover this port, the line I49 also having an inwardly opening check valve I1I functioning for the purpose above explained as to valve 6 I The operation of the system is as follows: The generation of steam in the boiler I43 causes steam to flow through'the pipe I44 and into the steam main I45. As the steam progresses into the main I45 it displaces the air therein which flows into the vent valves I 55 lifts the valve disks I61 and discharges to the atmosphere thus venting the steam main before the radiators are vented. While the vent valve I65, which is open to the outlets of the-radiators, is also open to the steam main I45, this valve remains closed during the venting of the air from the steam main because the disk I10 is heavier than the disks I6I. Upon the passage of steam into both valves I55 and the heating of the expansion elements I62 therein the valves I64 close the vents I60 and upon rise of pressure of steam in the system valve I65 automatically opens to vent the radiators I'41. Thus the steam line will become completely filled with steam before any steam can enter any of the radiators and when the steam line thus becomes filled with steam, steam will. start to enter all of the risers I46 simultaneously thus heating all of the radiators simultaneously.

Itwill be understood that it is not necessary that both oft'hevalves I55 vent at the same pressure so long, as they both vent at a pressure sub.- stantially'below that at which the vent I65 opens. Shouldvalves I55 vent at different pressures the oneventing at lower pressure will close, and the steam. will fill this end of the steam line first andltherefore fill the other end before the valve I65 opens to permit steam to flow into the radiators.

Referring to. the system shown in Figs. 12 and 13, theboiler I12 connects by a pipe I13 with a steam main I14 communicating with risers I15 openinginto the radiators I16 the outlets of which open into pipes I11 communicating with a return line I18. A return trap I 19 connects at its upper endzwithpipes I and I8I which open, respectively, into the steam main I14 and the return line I18, .andopens at its bottom into a pipe discharging into the bottom of the boiler I12.

At: the ends of the steam main I14'and the return line I18 are float-equipped thermostatic vent valves. I;82- comprising casings I83 containing mainand supplemental chambers I84 and I85, respectively, communicating through ports I86 inzthe top walls; of chambers I85, the pipe I" opening into the main chambers I84 and the pipe I18'openinginto the supplemental chambers I85.

Theuwater of condensation flowing in the pipe I14 returns, to the boiler I12 through the casings I83 andtocontrol this flow the valve structures I82 are providedwith valves I81 operated by floats I88: inthe chambers I84 and maintaining the chambers I closed to chambers I84 except when the, water of condensation accumulates in the chambers; I84 to such a height as to force the floats I 88lto valve-raising position.

The valves. I82 also comprise thermostatic means for venting the line I14 of air shown as ofv the same construction as the valves I55of the preceding figures, the outlet-port-controlling disks of which are represented at I89 and the expansioneelement-controlled valves at I90;

The-line. I18 is also provided with a vent valve I91; of the same construction as the vent valve I65: and operative to open position by. the exertion againstits outlet-port-controlling diskof greater pressure than required to open the disks I89 of valves I82 asin the'case of valve I65.

The' operation of the system now being describedxis the same as that shown in Fig. 9 except that the water in' the wet return line of Fig. 9: operatestoiprevent the'flow of air from-the team :maintinto the return line, whereas in the system of Fig. 12 the float valves actto prevent the flow of air from the steam Ih'aih into the return line.

The line I18 is also shown as provided with an inwardly opening check valve I92 which per forms the same function as that erformed by the check valve 6 I of Fig. 4.

It will be noted that as to those of the systemsabove described which involve the venting of the particular embodiments of my invention, I denot- Wish to be understood as intending to limit itthereto as the same may be embodied other forms of structure and the'stru'ctures shown va riously modified and altered withii-t depa'i 'tingfrom the spirit o'f my' invention.

What I claim as new, and desire to secui e by' Letters Patent, is:

1. A steam heating system comprising-a source of steam, a steam main connected with said source, a: plurality of radiators corinected with said steam main, and automatically operating means for maintaining any air which may bepresent in theradiators against escape therefrom until the steam main has become filledwitli-Starhi- 2'. A steam heating system comprising a sourceof steam, at steam main connected with said source, a plurality of radiators, means for vent ing air from the radiators,- independent means for venting the air from the steammain-and adapted to close bythepresence of stearit at said lastnamed means, said radiators being connected said- Steam main between said sourceand said second-named means; and means for sealing the radiator-venting means-enumerasteam main-venting means has been closed by the presence: of steam therein;

8; A steam heating systeni=comprising a source of steam, a steammainconnected with said source, a; plurality-"ot radiators; means for venting the air frorir the radiatorsop'erated by the-pres sure of steam in the radiators, independent meansfo'r' venting-the air from the steam rfiaihand adapted to: close bythe-presence of steam at said" last-named means, said radiators being? connected with said steam" main between-said source and said second-named means, and means forseal-ing'the radiator-venting means until said steam main venting means has been closedbythe presence of steam therein.

4, A steam heating system comprising asour'ce of steam. a steam connected: with said source, apmrauty of r'adiators, means for"vent--' ir'ig the air from the radiators; independent means for venting the air from the steam main,- said radiators beingi connected-with said steam main between said source andsaid second-named presence ornon pi esence of steam throughout said steam mainand controlling said first-named means and operative to maintain said first-named means inactive-to-vent the radiators until steam fills said steam 5; A steam heatirigsystem eomprisinga source of steam; steam mai connected" with said source; a plurality of radiators, meansrorvent:

active to vent said radiators until steam reaches ing the air from the radiators, and means'in communication with said steam main operative to permit the flow of air from said steam main and operated by the presence of steam at said last-named means to prevent the flow of steam through said main otherwise than to said radiators, said radiators being connected with said steam main between said source and said second-named means and said first-named means being so constructed and arranged as to be insaid last-named means.

. 6. A steam heating system comprising a source of steam, a steam main connected with said source and a plurality of radiators, means for venting the air from the radiators, and means whereby the steam is permitted to flow in said steam main and vent the air therefrom and thereafter automatically close to prevent the passage of steam from said steam main except to said radiators, said radiators being connected with said steam main between said source and said second-named means and said first-named means being inactive to vent the radiators of the air therein until said steam main becomes filled with steam.

'7. A steam heating system comprising a source of steam, a steam main connected with said source, a. plurality of radiators, vent means controlling the venting of the air from the radiators, and thermostatic vent means for said steam main for controlling the venting of the air therefrom, said radiators being connected with said steam main between said source and said second-named means and said first-named means being so constructed and arranged that said radiators remain closed against the escape of air therefrom until the air is vented from said steam-main.

8. A steam heating system comprising a source of steam, a steam main connected with said source, a plurality of radiators, vent means controlling the venting of the air from the radiators, thermostatic trap means for said steam main, said radiators being connected with said steam main between said source and said thermostatic trap means, and suction means in communication with said thermostatic trap means, said suction means being operative to create a lower pressure at the outlet of said thermostatic trap means than the pressure at the outlet of said vent means.

9. A steam heating system comprising a source of steam, a steam main connected with said source, a plurality of radiators, thermostatic trap means for said steam main, vents associated with the radiators, said radiators being connected with said steam main between said source .and said means, a return pipe connected with said steam main thermostatic trap means, a second return pipe connected with said radiator vents, and a water leg in said second return pipe, said water leg being arranged to set up a resistance to the escape of air from said second return pipe which resistance is not present in said first referred to return pipe.

10. A steam heating system comprising a source of steam, a steam main connected with said .source, a plurality of radiators, thermostatic trap means for said steam main, vents associated with the radiators, said radiators being connected with said steam main between said source and said means, a return pipe connected with said steam main thermostatic trap means, a second return pipe connected with said radiator vents, a water leg in said second return pipe, and suction means in communication with said return pipes, said water leg being arranged to set up a resistance to the withdrawal of air from said second return: pipe by said suction means which resistance is not present in said first referred to return pipe.

11. A steam heating system comprising a source of steam, a steam main connected with said source, a plurality of radiators, return pipes one of which is connected with said radiators and the other of which connects with said steam main, and thermostatically controlled means in communication with said return pipes operative to maintain the return pipe for said steam main open to the atmosphere and the other of said return pipes closed to the atmosphere until steam reaches said means and to close to the atmosphere the one of said return pipes for said steam main and open the other of said return pipes to the atmosphere when steam reaches said means, said radiators being connected with said steam main between said source and said means.

12. A steam heating system comprising a source of steam, a steam main connected with said source, a plurality of radiators, thermostatic traps associated with the radiators, return pipes one of which is connected with said traps and'the other of which connects with said steam main, and thermostatically controlled means in communication with said return pipes operative to maintain the return pipe for said steam main open to the atmosphere and the other of said return pipes closed to the atmosphere until steam reaches said means, and to close to the atmosphere one of said return pipes for said steam main and open the other of said return pipes to the atmosphere when steam reaches said means, said radiators being connected with said steam main between said source and said means.

13. A steam heating system comprising a source of steam, a steam main connected with said source, a plurality of radiators connected with said steam main, means for maintaining any air which may be present in the radiators against escape therefrom until the steam main has become' filled with steam and comprising a return line in which vacuum is produced in the cooling of the radiators, and an inwardly opening check valve for relieving the vacuum in said return line by permitting the re-entry of air thereinto.

14. A steam heating system comprising a source of steam, a steam main connected with saidsource, a plurality of radiators, a return line connected with the outlets of said radiators, thermostatically controlled means for venting the air from said steam main, said radiators being connected with said steam main between said source and said means, and air-venting means for said return line inactive to vent the air from said return line until said thermostatically controlled means become closed by the presence of steam thereat.

15. A steam heating system comprising a source of steam, a steam main connected with said; source, a plurality of radiators, a return line connected with the outlets of said radiators, said steam main connecting with said return line, a water seal in the return line closing the passage of air from said steam main to said return line, thermostatic means for venting the air from said steam main, said radiators being connected with said steam main between said source and said second-named means, and air-venting means for said return line inactive to vent the air from said return line until said thermostatic means be-: come closed by steam at said thermostatic means.

16. A steam heating system comprising a source.

of steam, a steam main connected with said source, a plurality of radiators, a return line connected with the outlets of said radiators, floatcontrolled means communicating with said steam main and said return line for maintaining water sealed communication between said steam main and said return line, thermostatic means for venting the air from said steam main, said radiators being connected with said steam main between said source and said second named means, and air venting means for said return line inactive to vent the air from said return line until said thermostatic means become closed by steam at said thermostatic means.

17 A steam heating system comprising a source of steam, a steam main connected with said source, a plurality of radiators, a single vent device for venting air from the radiators, independent means for venting the air from the steam main and adapted to close by the presence of steam at said last-named means, said radiators: being connected with said steam main between said source and said means, and means for sealing the radiator-venting means until said steammain-venting means has been closed by the presence of steam therein.

18. A steam heating system comprising a source of steam, a steam main connected with said source, a plurality of radiators, a single vent device for venting air from the radiators, independent means, comprising a plurality of vent devices, for venting the air from the steam main and adapted to close by the presence or steam at said last-named means said radiators being connected with said steam main between said source and said vent means, and means for sealing the radiator-venting means until said steam-mainventing has been closed by the presence of steam therein.

19. A steam heating system comprising a source of steam, a steam main connected with said source, a plurality of radiators, thermostatic trap means for said steam main, said radito the escape of air from said second return line which resistance is not present in said first-referred-to return line.

20. A steam heating system comprising a source of steam, a steam main connected with said source, a plurality of radiators, vent means controlling the venting of the air from the radiators to the atmosphere, thermostatic trap means for said steam main, said radiators being connected with said steam main between said source and said thermostatic trap means, and suction means in communication with said thermostatic trap means, said suction means being operative to create a lower pressure at the outlet of said thermostatic trap means than the pressure at the outlet of said thermostatic vent means.

21. A steam heating system comprising a source of steam, a steam main connected with said source, a plurality of radiators connected with said steam main, radiator venting means, steam-main-venting means, and means causing said radiator venting means to be inactive to vent air from the radiators while said steammain-v-enting means are operating to vent air from the steam main.

22. A steam heating system comprising a source of steam, a steam main connected with said source, a plurality of radiators, superatmospheric pressure operated vent means controlling the venting of the air from the radiators, thermostatic trap means for said steam main, said radiators being connected with said steam main between said source and said thermostatic trap means, and suction means in communication with 40 said thermostatic trap means.

FRED I. RAYMOND. 

